Ignition circuit device



y 1959 G. A. BUON 2,888,574

IGNITION CIRCUIT DEVICE Filed Dec. 51, 1956 GEOEg E 0N F/6. 4 I A 4/ AORNEY United States Patent M 2,833,574 TGNTIION CIRCUIT DEVICE GeorgesAndr Buon, Queens, N.Y. Application December 31, 1956, Serial No.631,839 11 Claims. Cl. 307- This invention relates to ignition circuitdevices, and more particularly to booster devices for improving ignitioncircuit service during the initial periods of operationthereof.

.The invention contemplates providing vehicles which employ ignitioncircuits with optimum ignition condi tions each time the engine of thevehicle is started and takes particular consideration of the adverseconditions to which vehicles and their elements can be exposed.

During the starting period of an engine, the drain upon its electricalstarting system is severest. For example, in an automobile, when theignition switch is employed to close the electrical circuit, thestarting motor and the ignition system constitute simultaneous loads onthe battery. Moreover, under adverse conditions such as low ambienttemperatures, the electric starting motor has a heavy mechanical loadimposed upon it so that the starting motor in turn increases its drainupon the battery which itself is at its lowest electrical capacity dueto the low temperature.

, An object of the invention is to avoid severe drains on the starterpower supply by the provision of a temporary supplementary supply to theignition circuit which is effective only during the starting period ofthe engine with which it is associated.

Otherwise expressed, it is an object of the invention to provide animproved ignition device for facilitating engine starting especiallyunder adverse conditions.

A further object of the invention is to provide a unit which can beinstalled in known ignition circuits to cooperate therewith to achievethe various improvements which inure to the benefit of ignition circuitsincorporating features of the invention.

To provide its various benefits, the invention in its variousembodiments involves the use of a supplementary power supply which iseffective in the ignition circuit, in combination with the usual powersupply of the starting device of an engine, during the starting periodof the engine. In combination with the supplementary supply, there isfurther provided a switching means which is operative to render thesupplementary supply ineflective after a period of time has elapsedfollowing the starting operation initiation.

Advantageously, the intermittent use of the supplementary or boostersupply enables a very efficient use of this component. Thus, since thebooster is not always in use, it is not necessarily of the same strengthor reserve as would be required for full time operation. Moreover, thelife of this unit is accordingly extended.

A further advantage of the means provided in accordance with theinvention is that, since they can be installed in existing devices forcooperation therewith, they can be independently and economicallyassembled.

Other objects and advantages of the invention will be shown in thefollowing detailed description of a preferred embodiment of theinvention, this and other embodiments of the invention being illustratedin the accompanying drawing in which:

Patented May 26, 1959 Figure 1 is a partially schematic and partiallydiagrammatic illustration of an ignition circuit embodying featunes ofthe invention;

Figure 2 is a pictorial view of an ignition device in which theinvention is employed in correspondence with the circuitry shown in Fig.l;

Figure 3 is a partially pictorial and partially schematic illustrationof another embodiment of the invention featuring a variation in theswitching means for controlling the operation of the booster supply; and

Figure 4 represents still another embodiment of the invention alsofeaturing a variation in the switching means.

The ignition device and circuit shown in Figs. 1 and 2 includes abattery 10, an ignition switch 12, an ignition coil 14, a breaker 16, adistributor 18, and spark plugs 20. In known ignition devices, thebattery 10 is conpled to the ignition switch 12 by a connection 22, the

switch 12 controlling the supply of power to a starting motor (notshown) and via the ignition coil 14 to the breaker 16 and to thedistributor 18. Connections 24 and 26 are provided between the coil 14and the distributor 18, and the breaker 16 and coil 14, respectively.These components are known in various arrangements of which theillustrated arrangement is exemplary only, the invention being equallyapplicable to the various types of devices in a manner similar to thatwhich will be shown. For present purposes, the relay 86 illustrated inthe circuit will be assumed to be a short circuit.

In accordance with the invention, there is further provided a device 29including a booster voltage supply or battery 28 and a switch means(generally indicated) 30, these components being coupled intermediatethe ignition switch 12 and coil 14 by leads 32 and 34. Also provided arethe leads or connections 3640.

The switch means 30 includes the heat generating element or heater 42which may simply be a resistor, and a heat responsive element 44 whichmay be a bimetallic strip. There are commercially available unitscapable of serving as the switch means 30 but the unit may be such as isillustrated in Fig. 2 by the micro-switch 46 including contacts 48 and50 and blade 52.

In fact, the structures of Figs. 1 and 2 differ slightly in that in Fig.1 the bimetallic strip is a conductor whereas in Fig. 2 the bimetallicstrip operates the microswitch within which the blade 52 acts as theconductor. However, in principle, the two devices operate almostidentically.

In use, the batteries 10 and 28 are connected in their respectivecircuits so that they are series adding when the ignition switch 12 isclosed. Moreover, the closing of switch 12 couples the heater 42 to thebattery 10.

As a consequence thereof, When the ignition switch 12 is closed, thecombined voltages of the batteries 10 and 28 are applied to the ignitioncoil 14 and to other utilization devices in the circuit. The battery 10is applied to the heater 42 which generates suflicient heat in adeterminable period of time to cause a switching action by means of thebimetallic strip 44. This switching action is very nearly instantaneousin the micro-switch 46 and also in the element 44 of Fig. l inaccordance with known spring biasing provisions.

Thus, in accordance with the principles of the invention, an action isprovided whereby a booster supply is employed in an ignition circuitduring the starting period and for a. period of time following theclosing of the ignition switch. The auxiliary voltage provided by thebooster 28 is preferably fifty percent of the normal voltage supply soas to compensate for the voltage drop in the main power supply or to addthereto during the warmup period. Trial has shown that the utilizationelements of ignition circuits can readily absorb this additional powerwithout deleterious efiects.

The period during which the booster supply is employed is generallydefined by the expected length of the warmup period and the boostermechanism is readily calibrated with the length of this period by theparameters of the heater and the heat responsive element as well asthespacing therebetween. It will be noted, however, that the choice ofthese parameters establishes an unalterablepredetermined period of timefor the booster application unless, for example, the heater is providedin variable form. It is conceivable, notwithstanding the aboveprovisions, that another form of time control may be desirable and forthis reason the invention contemplates an analogue control which may be,for example, a control of the period in response to a quantity of energyor the like generated or existing in the engine itself.

Accordingly, there is illustrated in Fig. 3 a mechanism in which theperiod of booster application can be variable and in which the period iscontrolled by a quantity of energy supplied by the engine. The circuitemployed in this embodiment consists of the same elements as in thepreviously described embodiment and in similar manner the boosterbattery 28 is connected in series with the main battery or the boosterbattery is by-passed by means of the leads 54 and 56, respectively ascontrolled by operation of the micro-switch 46.

In this embodiment, however, the bimetallic strip 44 responds to thetemperature of the exhaust manifold 58 of the engine 60 which functionis achieved through the simple expedient of mounting the switch and theheat responsive element on and adjacent the manifold. As a consequencethereof, the booster battery operates during the initial warmup periodof the engine and cuts out when the exhaust manifold reaches apredetermined temperature.

It is obvious that various mounting positions can be used to accommodatethe switch and its heat responsive element and that the manifold isillustrated for exemplary purposes only. The illustration should beconsidered as one of a device wherein the period of time during whichthe booster supply is employed is variable in accordance with operatingconditions. This embodiment more suitably takes into account such thingsas weather conditions and the like.

Attention is next directed to the fact that the embodiments which havebeen described have each employed heat responsive elements. It is not tobe assumed, however, that the invention is thus limited and, by way ofexample, the invention is further illustrated in Fig. 4 wherein is shownan electrical time delay circuit which is rendered operative upon theclosing of an ignition switch and maintains the booster supply effectivefor a determinable period of time.

The device of Fig. 4, apart from the elements previously described,includes the contacts 62 and 64 and the blade 66 of a relay 68 whosecoil is 70 is coupled to a transistor 72.

The transistor, as is known, comprises a collector electrode 74, anemitter electrode 76 and base electrode '78, the latter being coupledthrough a capacitor 80 and a resistor 82 to ground. A resistor 34 ofhigh value can be used in parallel with capacitor 80 to enable thecomplete discharge thereof when the circuit is at rest.

The emitter electrode 76 is connectible by theignition switch 12 to thebattery 10 and, when the switch is closed, the transistor 72 conductsthereby activating the relay 68 so that the blade 66 is transposed fromthe contact 62 to the contact 64 in order to connect the booster battery23 in series with the battery it).

Once the ignition switch has been closed, the capacitor 80 commences tocharge and reaches a condition at which the transistor is biased tocutoff after a determinable period of time dependent upon the values ofthe capacitor and resistor. With the transistor 'cut olf, the coil 70 nolonger operates to retain the blade 66 on the contil tact 64 and theblade returns to the contact 62 to remove the booster 28 from thecircuit.

A further circuit which can be used is illustrated in Fig. 12-25, page462 of Transistor Electronics by 1.0, Endres, Zawels, Waldhauer andCheng; Prentice-Hall, Inc.; 1955. In this circuit, the relay can beconnected to the output terminal with the ignition circuit beingconnected to the voltage source (Vcc).

The devices which have been shown and described have in common theutilization of a booster supply which is employed for a finite period oftime following the initiation of the starting of an engine by means ofclosing the associated ignition switch. The period of time may bepredetermined or it may vary in accordance with operating conditions andthe like. The device may be heat responsive or it may be controlled byother means or forms of energy.

The functions of the devices of the invention include providing anadditional source of voltage to a main source of power for the startingof an engine or the like at the time during which such assistance isespecially required. The use of the invention is especially noteworthyunder adverse conditions. Advantageously, the booster supply is renderedineffective and is thus conserved after its objectives have beenachieved.

The incorporation of accessories in the ignition circuit is of littleconsequence since the devices of the invention can readily be modifiedto accommodate the same. Assuming, therefore, that an accessoryrepresented by the lamp 86 (see Figs. 14) is incorporated into theignition circuit so as to present a discharge path for the boosterbattery 28, a relay 8-8 can be simply added to the circuit so that thedischarge circuit for the battery 28 is open excepting during the warmupperiod as explained above.

There will now be obvious to those skilled in the art many modificationsand variations utilizing the principles set forth and realizing many orall of the objects of the invention, but which do not depart essentiallyfrom the scope of the invention as defined in the following claims.

What is claimed is:

l. A booster device for an engine ignition circuit provided with abattery, an ignition switch coupled to the battery and a utilizationdevice adapted for being operatively coupled to the battery, saidbooster device comprising a booster voltage source, circuit means fornormally coupling said booster voltage source operatively with saidbattery to provide said utilization device with an adequate source ofpower with said ignition switch closed, and switch means in said circuitmeans, said switch means including means for being actuated at theclos-. ing of the ignition switch to commence a delay period andrendering said booster voltage source ineffective following the period.

- 2. A device as claimed in claim 1 wherein said switch means renderssaid booster voltage source ineffective a predetermined period of timefollowing the closing of said ignition switch. 7

3. A device as claimed in claim 2 wherein said switch means isthermal-responsive for rendering said booster voltage sourceineffective.

4. A device as claimed in claim 2 wherein said switch means is anelectro-mechanical device for providing a switching operation after adeterminable time delay.

5. A device as claimed in claim 2 wherein said booster voltage source isa booster battery.

6. A device as claimed in claim 5 wherein said circuit means normallycouples said booster battery in series with said ignition circuitbattery and said switch means and said switch means operates to switchsaid booster battery out of the circuit a predetermined period of timeafter the ignition switch is closed.

7., A device as claimed in claim 6 comprising a source of heat andwherein said switch means comprises a heat responsive element coupled insaid circuit means and responsive to said source of heat for switchingsaid booster battery into and out of the circuit.

8. A device as claimed in claim 7 wherein said switch means comprises aheat generating element which is coupled to said ignition circuitbattery by means of said ignition switch, said heat generating elementbeing cooperative with said heat responsive element to cause a switchingoperation a determinable period of time following the coupling of saidheat generating element to said ignition circuit battery by the closingof said ignition switch.

9. A device as claimed in claim 1 wherein said switch means isresponsive to an external source of heat.

10. A device as claimed in claim 6 wherein said switch means is anelectro-mechanical device including a relay 6 for switching said boosterbattery into and out of said circuit and a time delay circuit forcontrolling the operation of said relay.

11. A device as claimed in claim 10 comprising a transistor coupled tosaid relay and by said ignition switch to said ignition circuit batteryand a resistor-capacitor circuit coupled to said transistor to enablesaid transistor to pass power from said ignition circuit battery to saidrelay for only a determinable period of time after said 10 ignitionswitch is closed.

References Cited in the file of this patent UNITED STATES PATENTS

